1. Field of the Invention
The invention relates to improved branch connections on flexible rubber tubes or pipes.
It is known that flexible vulcanized rubber based tubes or pipes used in the motor car industry, in particular but not exclusively those connected between the engine and the radiator for conveying the cooling fluid, must frequently comprise drain or branch connections which, whatever their use, require a junction or tapping on the main pipe. To form these tappings, it has already been proposed to cut the main pipe, to fit the two parts of the pipe onto the arms of a plastic material or metal T joint and the branch pipe on the body of a T then to secure them by means of clamping collars fixed close to the ends of the pipe sections. This very simple and low cost device however requires three assembly operations and the provision of an assembly line for the corresponding members, whereas present day techniques in the motor car industry seek to do away with these operations and the management which they imply of loose parts.
2. Description of the Prior Art
Therefore it has been proposed to replace the plastic T device by a branch connection obtained by molding a rubber coating about a part at least of a rigid tubular insert forming part of the branch connection, as described for example in FR-A-2 549 196. Such a method makes it possible to obtain satisfactory and widely used branch connections. However, their use is sometimes limited by their cost which in some cases is higher than the prior T, and this is why the applicant has sought to improve the existing method so as to lower the price of the devices obtained while guaranteeing the quality of the manufactured products, in particular in so far as the absence of leaks are concerned of the fluid flowing through the flexible tube or pipe.